1 Field of Invention
The invention relates generally to machines for creating laminated structures of reinforced composites, where the laminar plys are detruded by a presser member, for example, a roller or skidding shoe. In particular, the invention relates to machines for creating laminated structures where the laydown surface has a changing contour, especially across the presser member face.
2 Prior Art Information
It is known in machines for producing composites structures, for example, composite tape laying machines, that the tape laying head is usually oriented around the tape laying path, and the presser member face will thereby remain generally parallel to the tape surface. Where the tape laydown surface experiences contour changes across the presser member face, it has been known in the art to provide an elastomeric tire to a roller, and to provide a similarly deformable skin to a presser member shoe.
U.S. Pat. No. 4,601,775 illustrates a tape presser member assembly which has an internal force divider mechanism carried by an axle for dividing the frame pressing force, i.e., a radial force of the axle directed against the work surface, into at least two separate radial components, where the components are manifested through movable solid elements (spherical ball joints) into a distortable elastomeric presser strip which spans the movable members Thus, the assembly may universally adapt to a variety of surface contours occuring across the presser member face, i e., across the width of a structural tape.
U.S. Pat. No. 4,351,688, depicts a tape laying head which slits tape longitudinally into equal width strips, and each strip may be selectively severed to create approximate forms with the severed ends. The head contains a segmented roller system whereby individual rollers may be impressed on their respective strips until the strip length runs out, at which time the respective roller is pulled upward. The system provides for control of pressure on the tails of cut segments. However, the rollers are individually powered by air cylinders, and are automatically lifted by springs which bias the rollers in an upward direction, away from the laydown surface. The rollers are not compliant to ride on a variety of surface contours across the tape width, but rather are either "on", or "off".
Applicant has identified a need for a presser member which can smoothly conform to a changing surface contour across a presser member face which has a relatively simple mechanism obviating the need for individual segment power units, and which has a relatively low inertia to permit rapid acceleration and deceleration of the presser member segments while the tape laying head can "catch up" when its large mass is able to respond to surface contour changes.